<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <title>Document</title>
  <style type="text/css">
    .container {}

    .container .cart {
      width: 300px;
      /*background-color: lightgreen;*/
      margin: auto;
    }

    .container .title {
      background-color: lightblue;
      height: 40px;
      line-height: 40px;
      text-align: center;
      /*color: #fff;*/
    }

    .container .total {
      background-color: #FFCE46;
      height: 50px;
      line-height: 50px;
      text-align: right;
    }

    .container .total button {
      margin: 0 10px;
      background-color: #DC4C40;
      height: 35px;
      width: 80px;
      border: 0;
    }

    .container .total span {
      color: red;
      font-weight: bold;
    }

    .container .item {
      height: 55px;
      line-height: 55px;
      position: relative;
      border-top: 1px solid #ADD8E6;
    }

    .container .item img {
      width: 45px;
      height: 45px;
      margin: 5px;
    }

    .container .item .name {
      position: absolute;
      width: 90px;
      top: 0;
      left: 55px;
      font-size: 16px;
    }

    .container .item .change {
      width: 100px;
      position: absolute;
      top: 0;
      right: 50px;
    }

    .container .item .change a {
      font-size: 20px;
      width: 30px;
      text-decoration: none;
      background-color: lightgray;
      vertical-align: middle;
    }

    .container .item .change .num {
      width: 40px;
      height: 25px;
    }

    .container .item .del {
      position: absolute;
      top: 0;
      right: 0px;
      width: 40px;
      text-align: center;
      font-size: 40px;
      cursor: pointer;
      color: red;
    }

    .container .item .del:hover {
      background-color: orange;
    }
  </style>
</head>

<body>
  <div id="app">
    <div class="container">
      <my-cart></my-cart>
    </div>
  </div>
  <script type="text/javascript" src="js/vue.js"></script>
  <script type="text/javascript">
    var CardTitle = {
      props: ['uname'],
      template: `
      <div class="title">{{uname}}的商品</div>
      `
    };
    var CardList = {
      props: ['list'],
      template: `
      <div>
          <div :key="item.id" v-for="item in list" class="item">
            <img :src="item.img"/>
            <div class="name">{{item.name}}</div>
            <div class="change">
              <a href="" @click.prevent="sub(item.id)">－</a>
              <input type="text" class="num" :value="item.num" @blur="changeNum(item.id,$event)"/>
              <a href="" @click.prevent="add(item.id)">＋</a>
            </div>
            <div class="del" @click="del(item.id)">×</div>
          </div>
        </div>
      `,
      methods: {
        changeNum: function (id, event) {
          // console.log(id,event.target.value);
          this.$emit('change-num', {
            id: id,
            num: event.target.value,
            type: "change"
          });
        },
        del: function (id) {
          // 不应该在子组件中操作props中的数据
          // 把id传递给父组件
          this.$emit('cart-del', id);
        },
        sub: function (id) {
          this.$emit('change-num', {
            id: id,
            type: "sub"
          });
        },
        add: function (id) {
          this.$emit('change-num', {
            id: id,
            type: "add"
          });
        }

      }
    };
    var CardTotal = {
      props: ['list'],
      template: `
        <div class="total">
          <span>总价：{{total}}</span>
          <button>结算</button>
        </div>
      `,
      computed: {
        total: function () {
          // 计算商品的总价
          let total = 0;
          this.list.forEach(e => {
            total += e.price * e.num;
          });
          return total;
        }
      }
    };

    Vue.component('my-cart', {
      data: function () {
        return {
          uname: "foo",
          list: [{
            id: 1,
            name: 'TCL彩电',
            price: 1000,
            num: 1,
            img: 'img/a.jpg'
          }, {
            id: 2,
            name: '机顶盒',
            price: 1000,
            num: 1,
            img: 'img/b.jpg'
          }, {
            id: 3,
            name: '海尔冰箱',
            price: 1000,
            num: 1,
            img: 'img/c.jpg'
          }, {
            id: 4,
            name: '小米手机',
            price: 1000,
            num: 1,
            img: 'img/d.jpg'
          }, {
            id: 5,
            name: 'PPTV电视',
            price: 1000,
            num: 2,
            img: 'img/e.jpg'
          }]
        }
      },
      template: `
        <div class="cart">
          <cart-title :uname="uname"></cart-title>
          <cart-list :list="list" @cart-del="delCart($event)" @change-num="changeNum($event)"></cart-list>
          <cart-total :list="list"></cart-total>
        </div>
      `,
      components: {
        'cart-title': CardTitle,
        'cart-list': CardList,
        'cart-total': CardTotal,
      },
      methods: {
        delCart: function (id) {
          console.log(id);
          // 根据id删除list中对应的数据
          // 1.找到id所对应数据的所有
          let index = this.list.findIndex(item => {
            return item.id == id;
          });
          // 2.根据索引删除对应数据
          this.list.splice(index, 1);
        },
        changeNum: function (val) {
          // 分为三种情况: [输入域变更,加号变更,减号变更]
          // console.log(val)
          if (val.type == "change") {
            // 根据子组件传递过来的数据,更新list中对应的数据
            this.list.some(item => {
              if (item.id == val.id) {
                item.num = val.num;
                // 终止遍历
                return true;
              }
            });
          } else if (val.type == "sub") {
            this.list.some(item => {
              if (item.id == val.id) {
                if(item.num > 0 ){
                  item.num -= 1;
                }
                // 终止遍历
                return true;
              }
            })
          } else if (val.type == "add") {
            this.list.some(item => {
              if (item.id == val.id) {
                item.num += 1;
                 // 终止遍历
                 return true;
              }
            })
          }

        }
      }
    });
    var vm = new Vue({
      el: '#app',
      data: {

      }
    });

  </script>
</body>

</html>